Thoracic Injury Rule out Criteria in Prediction of Traumatic Intra-thoracic Injuries; a Validation Study

Introduction: Doing Chest X Ray (CXR) for all trauma patients is not efficient and cost effective due to its low diagnostic value. The present study was designed aiming to evaluate the diagnostic accuracy of thoracic injury rule out criteria (TIRC) in prediction of traumatic intra-thoracic injuries and need for CXR. Method: The present study is a prospective cross-sectional study that has been carried out to evaluate the accuracy of TIRC model in screening blunt multiple trauma patients in need of CXR for ruling out intra-thoracic injuries. Results: 1518 patients with the mean age of 33.53 ± 15.42 years were enrolled (80.4% male). The most common mechanisms of trauma were motor car accident (78.8%) and falling (13.6%). Area under the ROC curve, sensitivity, and specificity of model in detection of traumatic thoracic injuries was 0.95 (95% CI: 0.93 – 0.97), 100 (95% CI: 87.0 – 100), and 80.1 (95% CI: 78.0 – 82.1), respectively. Brier score for TIRC was 0.02 and its scaled reliability was 0.0002. Conclusion: Findings of the present study showed that TIRC has high accuracy in prediction of traumatic intra-thoracic injuries and screening patients in need of CXR.

Rate dependent left bundle branch block: the pattern of myocardial perfusion SPECT

We report myocardial perfusion SPECT pattern in four subsequentpatients with rate dependent left bundle branch block(LBBB). Three females and one male (aged 48, 51, 63 and 67years) were studied. None of the patients had history of typicalchest pain and all suffered from atypical chest pain or dyspneaon exertion. All patients were tested for baseline and serial heartrate, blood pressure, and electrocardiogram recordings. Theexercise treadmill tests (ETT) were carried out under the strictsupervision of a cardiologist, a nuclear medicine physician andclose availability of an expert cardio-pulmonary resuscitation teamand cardiac care unit within just few seconds. Maximal stress test(at least 85% of calculated heart rate, following development ofLBBB) was achieved in all four patients according to standardBruce protocol. No adverse cardiac events were noted and allETT stress protocols terminated completely and safely. Myocardialperfusion SPECT imaging showed no evidence of reversibleperfusion defects. The only patient with past history of exerciseinduced LBBB showed nonreversible perfusion defects in theseptal and anteroseptal regions and mild LV cavity dilatation. Thelimited number of patients enrolled in our study does not allow us todraw a definite conclusion. Despite the presence of false-positivedefects in myocardial perfusion SPECT in patients with sustained  LBBB, such a finding is not a consistent finding in patients withrate dependent or exercised-induced LBBB, unlike that which weexpected to see. Maybe it is possible to continue ETT for thosepatients undergoing myocardial perfusion scintigraphy and developingrate dependent LBBB.We report myocardial perfusion SPECT pattern in four subsequentpatients with rate dependent left bundle branch block(LBBB). Three females and one male (aged 48, 51, 63 and 67years) were studied. None of the patients had history of typicalchest pain and all suffered from atypical chest pain or dyspneaon exertion. All patients were tested for baseline and serial heartrate, blood pressure, and electrocardiogram recordings. Theexercise treadmill tests (ETT) were carried out under the strictsupervision of a cardiologist, a nuclear medicine physician andclose availability of an expert cardio-pulmonary resuscitation teamand cardiac care unit within just few seconds. Maximal stress test(at least 85% of calculated heart rate, following development ofLBBB) was achieved in all four patients according to standardBruce protocol. No adverse cardiac events were noted and allETT stress protocols terminated completely and safely. Myocardialperfusion SPECT imaging showed no evidence of reversibleperfusion defects. The only patient with past history of exerciseinduced LBBB showed nonreversible perfusion defects in theseptal and anteroseptal regions and mild LV cavity dilatation. Thelimited number of patients enrolled in our study does not allow us todraw a definite conclusion. Despite the presence of false-positivedefects in myocardial perfusion SPECT in patients with sustained  LBBB, such a finding is not a consistent finding in patients withrate dependent or exercised-induced LBBB, unlike that which weexpected to see. Maybe it is possible to continue ETT for thosepatients undergoing myocardial perfusion scintigraphy and developingrate dependent LBBB